Multiple-switch starter.



L. L. TATUM.

MULTIPLE; SWITGK STARTER.

Patented Apr; 20, 1909.

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L. L. TATUM. MULTIPLE SWITCH STARTER.

APPLICATION FILED HAY 20, 1907. BEIEWED IA]. 11, 1909.

Patented Apr. 20, 1909.

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L. L. TATUM. I MULTIPLE SWITCH STARTER.-

APPLIOA'IIOI FILED KAY 20, 1907. EEIEWBD IA]. 11, 1909- PatentedvApr.20, 1909. 3 SHEETS-SHEET 3.

WITNBS ES:

UNITED STATES PATENT ornron LEWIS L. TATUM, OF NORWOOD, OHIO, ASSIGNORTO THE CUTLER-HAMMER MFG. 00., OF

MILWAUKEE, WISCONSIN, A c- ORPORATION OF WISCONSIN.

MULTIPLE-SWITCH STARTER.

Specification of Letters Patent.

Patented April 20, 1909.

Application filed May 20, 1907, Serial No. 374,706. Renewed January 11,1909. Serial No. 471,777.

To all whom it may concern:

Be it known that I, Lnwrs L. TATUM, a citizen of the United States,residing at Yor-v wood, in the county of Hamilton and State of Ohio,have invented new and useful Improvements in Multiple-Switch Starters,of which the following is a full, clear, concise, and exact description,reference being had to the accompanying dravdng, formin a part of thisspecification.

My invention relates to improvements in motor controllers.

It is particularly applicable to controllers in which a plurality ofhand operated switches are used for controlling the resistance. a

According to the preferred form of my invention, I provide a pluralityof hand operated switches whichare preferably adapted to be closed in adefinite sequence to remove the starting resistance from the motorcircuit, and one of which is adapted to control the motor circuit. Theseswitches are maintained in their closed position, preferably by a lowvoltage device. This device acts upon failure of voltage or upon thedrop of voltage below a predetermined point to cause said switch whichcontrols the motor circuit to open. It is desirable in event thestarting resistance is left in circuit for longer than a predeterminedperiod that the circuit be opened. The resistance of motor startingdevices is usually made of wire which while it is of sufiicient capacityto carry the current for a short period, during the starting of themotor, is not of sufficient capacity to carry the current for a longperiod of time. In the present invention I prevent the leaving of thestarting resistance in circuit for longer than a predetermined period oftime by the provision of a plurality of switching devices which controlthe low voltage retaining device. These switching devices in theiroperative position tend to either open the circuit through the lowvoltage device, or close a short circuit'around the device, whereby thesame is caused to release the motor circuit switch and open the motorcircuit. I preferably provide one switching device for each of the handoperated switches except the last and when each hand operated switch ismoved to a closed position it moves its corresponding switching deviceto an inoperative position, but immediately releases the same to permitit to move toward operative position, to close a short circuit aroundthe low voltage device. However, before the switching device reaches itsoperative position, the next hand operated switch is closed which movesanother of the switching devices to inoperative position again openingthe short circuit. In this manner each hand operated switch is movedclosed before the preceding switching device moves to operativeposition. If the hand operated switches are not thus closed, theswitching devices will cause the low voltage device to release theswitches closed and open the circuit. The last hand operated switch tobe closed, is provided with a switch which when the hand switch isclosed, renders the switching devices inoperative. In this manner I amenabled to provide means which opens the circuit in event the startingresistance is left in circuit for a longer than a predetermined time.

For the purpose of disclosing my invention, I have illustrated in theaccompanying drawings one embodiment thereof.

In said drawings Figure 1 is a front elevation of the starting device ofmy invention, Fig. 2 is a section on the line 2-2 of Fig. 1. Fig. 3 is asimilar view with the switches open, Fig. 4 is a detailed view of thelatch mechanism for holding the switches in closed position, Fig. 5 is asectional top view of one of the switches and a top view of thecooperating rocking dogs, Fig. 6 is a detail of one of the rocking dogsemployed, Fig. 7 is a perspective view of one end of one of the rodscarrying a switching device. Fig. 8 is a detail perspective view of thecatch for operating the switching device, and Fig. 9 is a diagrammaticview of the circuit connections.

According to the embodiment of my in vention illustrated, the switches1, 1 1", 1, and 1 are suitably pivoted or journaled at one end and areprovided at the opposite end with suitable operating handles. I haveshown the several switches as journaled upon a shaft or rod 2, mountedin bearings 8, formed on brackets 4. The bracket 4 also supports a rod5, which is threaded through a rubber tube 6, which serves as a cushionor buffer against which the extended ends of the switches are adapted toimpinge when thrown 0 en. Each of the switches carries a contact c evice7 made preferably in the form of a number of strips of copper laid faceto face, the free ends being adapted to engage contact surfaces tocomplete the circuit. Upon the base board 8, which carries the variousoperating parts of the controlling device, and which is preferablyformed of slate, soapstone, or like material, is mounted a contact bar9, with which one end of the contact device 7 of each switch is adaptedto engage, the other end of said device being adapted to engage one ofthe contact terminals 10, 10 10 10, and 10 The contact devices 7 of theswitches 1 and 1 are preferably made wider than the remaining contactdevices as these devices are adapted to carry heavier current than theremaining devices. Upon the terminal 10 is provided a binding post 11 bywhich suitable electrical connection may be made therewith, and a likebinding post 12 is carried by the contact 10. Upon the terminal 10 ismounted a carbon block 13, and a similar carbon block 14 is mounted onthe end of the contact bar 9. The first switch has mounted thereonlaterally extending spring arms 15 and 16, supporting on the endsthereof, carbon blocks 17 and 18. When the switch is moved to close thecircuit, the block 13 engages the block 17, and the block 14 engages theblock 18, thereby closing the circuit from the terminal 10, to theterminal 9. The further movement from the switch 1 causes contactdevices to close together the terminals 10 and 9. Likewise, when theswitch 1 is moved outward, the contact devices 7 leaves the terminals 9and 10, before the carbon blocks separate so that any are which may beformed by the opening of the circuit will take place between the carbonblocks instead of between the metallic surfaces.

Near the up er end of the switch 1, a lug 19 is formed wl fich carries alaterally extending projection 20, which may take the form of a screw.Mounted upon the base board 8, above the arm 1 is a retaining magnet 21,having an armature 22 pivoted at 23, and having a laterally and upwardlyextending lug 24. "When the arm 1 is moved to close the circuit, theprojection 20 engages the side of the armature 22 to move the sameagainst the magnet pole, and the magnetism of the magnet 21 retains thearmature 22 in this po sition. The swinging of the armature 22 carriesthe lug 24 upon the exterior of the projection 20, so that saidprojection will rest in the slot formed between the lug 24 and the faceof the armature 22. So long as the magnet 21 remains energized, the armwill thus be held in a closed position. hen, however, the magnet 21 isdeenergized, the armature 22 will be released and the weight of the arm1 will carry the same to the position shown in Fig. 3, thereby rockingthe armature 22 upon its pivot as shown.

Mounted upon a rod or shaft 25, pivoted in suitable bearings upon thebase plate 8, are rocking dogs 26, 26 26 26. Each dog has its rear endso shaped as to engage the base plate and limit the downward movement ofthe dog when free. Upon the end of the dog, to the right hand side, anupwardly extending lip 27 is provided, which has its front edge curvedand its rear edge perpendicular to the upper surface of the dog. Theunder side of the dog has a lip 28 which extends throughout its entirelength, and is rounded off at the left hand edge. The switches 1 to 1inclusive, are each provided with a latch 29, pivoted to the arm at 30,in a slot 31, the walls of which slot limit the movement of the latchrelatively to the arm. The first switch 1 has no latch. Below the latchand formed integrally with the switch is a lug 32, proj ecting towardthe base plate and consisting of two parts 33 and 34. The part 33 is suared in section and flat upon the end, andv w lien the switch is in aposition to close the circuit presents a vertical surface. The upperpart of the part 34 is inclined or chamfered at an acute angle.

Mounted below the switches 1 to 1 are a plurality of switching devices,35, 35 35, and 35, one for each of the switches 1 to 1. Each of theswitches 35 to 35 is mounted upon a vertically movable arm 36, the lowerend of which is provided with a plunger 37 operating in a dash-pot 38,and the upper end of which is provided with a small cross arm or catch39. The dash-pot 38 is mounted upon suitable brackets 40, which isbolted or otherwise secured to the base plate 8, and which is providedwith a projection 41, forminga guide for the upper end of the rod 36.The rod 36 is provided with a flattened surface 42 which accommodates aprojection 43, formed in a guide stud 41, and which projection, engagingthe walls of the slot 42, limits the movement of the rod 36. The lowerprojecting end of each of the switches 1 to 1 carries a pivoted bellcrank lever 44, pivoted at 45, and having one arm thereof bifurcated asat 46 between which bifurcations the vertically movable arm 36 isadapted to fit. When the switch is in its open position the bifurcatedportions 46 are beneath the catch 39 of the rod, and as the arm is movedto its closed position and the bell crank arm 44 is moved upwardly,carrying with it the rod 36 and raising the switching device carriedthereby, until the bifurcations 46 are moved out of engagement with thecatch 39 by the moving of the switch arm to its final closed position.The moving of the bifurcations 46 out of engagement with the catch 39permits the vertically movable rod to drop and with it the switchingdevice carried thereby. The dash-pot 38 is constructed to retard thedownward movement of the rod, thereby retarding the downward movement ofthe switching device. The switching devices 36 to 36 are arranged tobridge pairs of contacts 47 and 47 48 and 48 49 and 49 and 50 and 50respectively. The last switch arm 1 has no corresponding switchingdevice, but carries a spring switch arm 51, which is adapted to engagewhen the switch arm is open, a stationary contact 52 mounted upon thebase 8.

I have diagrammatically illustrated in Fig. 9 the circuit connection forthe device above described. Referring now to Fig. 9, the contactterminal is connected with the positive side 53 of the supply mains. Thecontact terminal 10 is connected by the conductor 54 with one terminalof the armature 55 of the motor. The opposite terminal of the armatureis connected by conductor 56 with the negative side 57 of the supplymains. The contact bar 9 is connected by conductor 58 with one terminalof the magnet 21, and by the conductors 58 and 59, with one terminal ofthe field winding 60 of the motor, the opposite terminal of said fieldwinding being connected with conductor 56. The opposite terminal of themagnet 21 is connected through the high resistance 61, with the negativeside 57 of the line, and by a conductor 62, with the contact 47 a of thefirst switching device 35. The adjacent contacts of the remainingswitching devices 35 35 are connected together and the contact isconnected to the stationary contact 52. One section of resistance 63 isconnected between the contact bar 9 and the contact terminal 10 Aresistance 64 is connected between the contact terminals 10 and 10 andis divided into sections which are connected with the contacts 10 and10.

The operation of the device above described is as follows: Assuming thatit is desired to start the motor, the switch 1 is closed to first closethe circuit between the carbon blocks and finally to close together theterminals 9 and 10 directly through the contact device 7. The armature22 is enga ed and moved against the pole of the retaining mag; net 21,and, as the retaining magnet is energized, it serves to maintain theswitch arm in the closed position. At the same time that the switch 1 ismoved to its closed position, the bifurcations 46 of the lever 44,carried by the switch engage the projection 39 of the vertical rod 36opposite said switch, and raise said rod carrying with it the switchingdevice 35 and breaking the circuit at the contacts 47 and 47 Circuit isnow established from the positive side 53 to the contact 10, across thearm 1 to contact 9, thence by conductor 58, through the winding of themagnet 21 and through the high resistance 61, to the negative side 57 ofthe line. The magnet 21 is thus energized and holds the arm 1 in itsclosed position. Circuit is also established from the positive side 53of the line to contact 10, across the arm 1, contact 9, through theresistance 63 and 64, to contact 10, thence by conductor 54, through thearmature of the motor, and by conductor 56 to the negative side 57 ofthe line. The circuit is also established from the conductor 58, byconductor 59, through the field winding of the motor, to conductor 56.The motor is thus started. with all of the resistance in circuit. Whenthe switch 1 is moved to its closed position, the bifurcations 46 of thebell crank arm 44 disengage from the catch 39, permitting the rod 36 ofthe switching device 35 and the switch to move downwardly. This downwardmovement, however, is retarded by the dash-pot 38. In moving the switchto the closed position, the oblique wall 34 of the lug 32 thereofengages the under face of the first rocking dog 26 and raises the sameinto the position shown in full lines in Fig. 4. Before the switch 35moves into engagement with its contacts 47 a and 47, the second switcharm is closed and as the dog 26 is in its raised position, the latch 29of the switch 1 will ride over the lip 2-7 of the dog 26 and engage thevertical wall thereof, thereby holding the switch 1 in its closedposition. The closing of the switch 1 causes the bifurcations 46 of thearm 44 carried thereby to engage the vertical rod 36 of the switch 35and raise the rod as has been previously described, with respect to theswi ch 35*. V' hen the switch is finally closed, the catch 46 disengagesfrom the catch 39, permitting the rod and with it the switch 35" toagain move to its closed position. In closing the switch arm 1 theoblique wall 34 of the lug 32 thereof engages the next rocking dog 26raising the same in a position to be engaged by the latch 29 of theswitch arm 1 and in a similar manner each of the succeeding switch armsis closed. Also the closing of each switch arm raises its correspondingswitching device. It is necessary that each succeeding switch arm bemoved to its closed position before the switching device of thepreceding switch arm moves to its closed position. Otherwise theswitching device will drop and establish a short-circuit from thepositive side 53 of the line to contact 10, thence across the arm 1,through the shaft or rod 2, to the switch 1, thence to the switch 51,thence to stationary contact 52, across the switches 35 to 35 byconductor 62, through the high resistance 61, to the negative side ofthe supply main. This shortcircuits the magnet 21 and de energizes thesame, permitting the switches closed to open. If, however, each of theswitches 1 to 1 are closed before the sudtching devices 35 to 35 arepermitted to close,

the short-circuit will be always open, and the magnet will remainenergized. When the last switch is closed, the switch member 52 is movedoff of the stationary contact, thereby opening the short-circuit aroundthe magnet 21, and the magnet remains energized to hold all of theswitches in a closed position. It will thus be seen that by theprovision of the switching devices 35'" to 35 I am enabled to place atime limit upon the closing of each switch, thereby avoiding the heatingof the resistance unduly.

If it is desired to cut in the resistance and open the circuit throughthe motor, the retaining magnet 21 may be deenergized in any suitablemanner, and the switch 1 will be released and fly outward to theposition shown in Fig. 3. In moving outward, the first rocking dog 26 ispermitted to fall, and the latch 29 of the second switch 1 is thusreleased, and said switch likewise flies out. The second switch 1permits the second rocking dog 26 to fall, thereby releasing the thirdswitch. In a similar manner each switch releases the next succeedingswitch, until all of the switches have been released.

Any attempt to close one of the switches out of its regular order isprevented, due to the fact that the flat face 33 will engage the end ofthe rocking dog when the dog is in its lowermost position, and it isonly when the dog has been raised to its upper position that the flatface 33 will be permitted to pass beneath the end of the rocking dog.Moreover, unless the rocking dog is in the upper position, the latch 29will not engage the lip 27 upon the dog, and the rocking dog will beheld in the upper position only when the im mediately preceding switchhas been closed. The accidental or intentional closing of one of theswitches out of its regular order is thus effectually prevented.

It is obvious that various changes and modifications may be made in theconstruction and arrangement of my device as vary ing the electriccircuit, modifying the retaining device and the like, without departingfrom the spirit of my invention as set forth in the appended claims.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is: p

1. The combination with a plurality of switches adapted to be closed ina deiinite sequence, of a plurality of means for causing the circuit tobe opened through the switches closed when the next succeeding switchremains unclosed for a time longer than a predetermined period.

2. The combination with a plurality of switches, of a plurality of meansset by said switches for causing the switches to open when a part of theswitches remain unclosed for a longer time than a predetermined period.

3. The combination with a plurality of switches, of a retaining magnetfor holding the same, and a plurality of means successively set by saidswitches for causing said retaining magnet to permit the switches toopen when part of the switches remain open for a predetermined time.

4. The combination with a plurality of switches, of retaining meanstherefor, a plurality of devices tending to move to render saidretaining means inoperative after each switch is closed, one of saiddevices being adapted to be set upon the closing of each switch.

5. The combination-with a plurality of switches, of a retaining devicefor holding the same closed, and a plurality of devices one operated byeach switch for controlling said retaining device.

6. The combination with a plurality of switches, of a retaining meansfor holding the switches closed, and a plurality of devices onecontrolled by each switch for operating said retaining means to open theswitches unless each switch is closed within a predetermined time afterits preceding one.

7. The combination with a plurality of switches, of retaining means forholding the same closed, a plurality of devices each adapted to releasesaid retaining means within a predetermined period of time after beingset, certain ot'said switches, when actuated, being each adapted torender one of said devices operative, and means whereby the closing ofone of said switches will render all of said devices inoperative.

8. The combination with a plurality of switches, of an electroresponsivemeans for retaining said switches closed, and a plu rality of deviceseach adapted to render said BIGGt-IOIGSPOIISIVG means inoperative at apredetermined time after being set, certain of said switches, whenactuated, being each adapted to render one of said devices operative andone of said switches when closed being adapted to render said devicesinoperative.

9. In a motor controller the combination with a plurality of switches,of a resistance controlled thereby, a plurality of means, one

' set by each of said switches, having atendency to move to a positionto cause said switches to open the motor circuit and adapted to open themotor circuit unless all of the resistance is removed from the circuitwithin a predetermined time. 7

10. In a motor controller the combination with a resistance, of aplurality of switches for controlling said resistance, a switch amongsaid switches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of switching devices operatively connected with said lowvoltage device and adapted to cause said low voltage device to cause thecircuit to be opened unless the resistance is removed from circuitwithin a predetermined time.

11. In a motor controller the combination with a resistance, of aplurality of switches for controlling said resistance, a switch amongsaid switches controlling the motor circuit, a low voltage devicecooperating with said last mentioned switch whereby the same is operatedto open the motor circuit in event the voltage falls below apredetermined point, a plurality of switching devices operativelyconnected with said low voltage device and adapted to cause said lowvoltage device to cause the circuit to be openedunless the resistance isremoved from the circuit within a predetermined time, and means operatedupon the closing of the last switch for rendering such switching deviceineffective.

12. In a motor controller the combination with a resistance, of aplurality of switches for controlling the same, a switch among saidswitches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of switching devices operatively connected with said lowvoltage device and adapted to cause said low voltage device to cause thecircuit to be opened, mechanical connection between said switches andsaid switching devices, and means operated upon the closing of the lastswitch for rendering said switching devices inefi'ective.

13. In a motor controller the combination with a resistance, of aplurality of switches for controlling said resistance, a switch amongsaid switches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of switching devices, one adapted to be set by the closing ofeach switch except the last, operatively connected with said low voltagedevice and adapted to cause said low voltage device to cause the circuitto be opened, and means for timing said switching devices.

14. In a motor controller the combination with a resistance, of aplurality of switches for controlling the resistance, a switch amongsaid switches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, a

plurality of switching devices, one adapted to be set by the closing ofeach switch except the last, operatively connected with said low voltagedevice and adapted to cause said low voltage device to cause the circuitto be opened, means for timing said switching devices, and meansoperated upon the closing of the last switch for rendering saidswitching devices inefi ective.

15. In a motor controller the combination with a resistance, of aplurality of switches for controlling the same, a switch among saidswitches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of Witching devices operatively connected with said lowvoltage device and adapted to cause said low voltage device to cause thecircuit to be opened, mechanical connection between said switches andsaid switching devices, and means for timing said switching devices.

16. In a motor controller the combination with a resistance, of aplurality of switches for controlling said resistance, a switch amongsaid switches for controlling the mo tor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of switching devices operatively connected with said lowvoltage device and adapted to cause said low voltage device to cause thecircuit to be opened unless the re sistance is removed from circuitwithin a predetermined time, and means for timing the operation of saidswitching devices.

17. In a motor controller the combination with a resistance, of aplurality of switches for controlling the same, a switch among saidswitches for controlling the motor circuit, a low voltage devicecooperating with said switch whereby the same is operated to open themotor circuit in event the voltage falls below a predetermined point, aplurality of switching devices operatively connected with said lowvoltage device and adapted to cause said low voltage device to cause thecircuit to be opened, unless the resistance is removed from circuitwithin a predetermined period of time and mechanical connection betweensaid switches and said switching devices.

In witness whereof, I have hereunto subscribed my name in the presenceof two witnesses.

LEWIS L. TATUM. IVitnesses ALEX. H. Lmnnns, JULIA O. LooMIs.

